New to 5er, do you always hook up the sewer and gray tanks at a campground? or Do you hook up and keep valves closed until the tanks are full?

If you plan on staying for a few days I'd hook up the pipes but leave all the valves closed.

The best way to dump a black water tank is when it is at least 3/4 full. That way the water pressure really works well in cleaning out the tank.
If I stay at a site for 2 or 3 days is my limit on black water tank before I dump.

Dump grey water after you dump black water. That way the pipe gets cleaned out of any chunks. If you know what I mean.

Bottom line before going home from a weekend make sure your tanks are well flushed out especially the black. Oh put some fresh water back in black tank with some chemicals so you will have fresh smell next time you go out.

If I am going to be there for more than over night, yes I hook everything up. Open the gray tank valve(s) and leave the black tank valve closed. Evening before we leave I close all the valves and let the gray tanks fill a bit. When dumping I open the black valve first. Once it is drained I also then open the gray tank valves. This flushes the hose and lines out as much as possible. Close the valves, disconnect and store everything.

Most of the time I hook up the hose when initially setting up but sometimes I wait until the tanks need dumping. As mentioned above, keep the vavles closed until your tanks are at least ĺ's full. Dump black first, then grey.

I think the when is not as important as the how. All ways leave the black tank valve closed until you are ready to dump. This gives things a chance to break down alittle. If possible after dump you need to flush with water to clean out as much as possible from the bottom of the tank. As to the grey tank or tanks some keep the valve closed some open, I keep mine closed until ready to dump the reason is the added pressure of a full tank may help move any waste out of the tank.

I think the when is not as important as the how. All ways leave the black tank valve closed until you are ready to dump. This gives things a chance to break down a little. If possible after dump you need to flush with water to clean out as much as possible from the bottom of the tank. As to the grey tank or tanks some keep the valve closed some open, I keep mine closed until ready to dump the reason is the added pressure of a full tank may help move any waste out of the tank.

Times Two.

If I need to dump black before I leave for home and the tank is not full, I will run water into the tank until it is and then dump and flush.
Try to never dump a partly full black tank. Even with turbo flush its hard to get crud and paper off the sensors.

For the group...

I have been using Coleman brand paper and it is awful. It is expensive; most rolls are not perfed all the way across and fall apart coming off the roll; and don't dissolve worth a c...

Once it is drained I also then open the gray tank valves. This flushes the hose and lines out as much as possible.

Not too sure about this one. I was always told to close the black tank valve before flushing the gray. Reason was, you don't want to take a chance of contaminating the gray with black "stuff". Now, I won't claim to know the validity of this, or whether the two can mix, but why take the chance.

Not too sure about this one. I was always told to close the black tank valve before flushing the gray. Reason was, you don't want to take a chance of contaminating the gray with black "stuff". Now, I won't claim to know the validity of this, or whether the two can mix, but why take the chance.

You are correct.
After dumping black you close it and then open the gray.
Never have them both open at the same time.